Thread
Another SE/30... Y1 resistor (?)
Let me take a slightly different track. What is the bare minimum needed in the way of components - assuming the traces are okay - to get a disk to eject? And to get something to show up on the screen?
I need some baseline debugging environment. [Again, no expert but the traces don't look terrible to me. I also cleaned the vias.]
I need some baseline debugging environment. [Again, no expert but the traces don't look terrible to me. I also cleaned the vias.]
And: I think if there's a RAM issue, it'd be with SIM 1, where there's still a little corrosion under - I think. Can the screen start without RAM in SIM 1? Can it start without any RAM? It may also be a ROM issue -the ROM looks like it had water spilled on it although I don't know that that did any real damage to the chips or circuit.
Is there really no barebones guide/tutorial for this? For instance... how would I know if the 68030 is fried?
And actually, are there any good guides to dishwashing? I'm probably close to that point. I've used a good deal of vinegar, rubbing alcohol, scrubbing bubbles and distilled water. There are still some problem spots.
Is there really no barebones guide/tutorial for this? For instance... how would I know if the 68030 is fried?
And actually, are there any good guides to dishwashing? I'm probably close to that point. I've used a good deal of vinegar, rubbing alcohol, scrubbing bubbles and distilled water. There are still some problem spots.
This is pushing the edge of my knowledge and probably safety. I tested the voltage in a few places on the board:
(I didn't control for polarity so I'm just listing voltages)
Disk Port Pins 7/8 - 12V
Pin 5 (the 5V) - Nothing
UK4/6 both 5V
UC8 - 12 V
C1 - 5V
C3 - 5V
C4 - 5V
C5 - 5V
C6 - 0.5V
C7 - 5V
C8 - 5V
C9 - Nothing
C11 - 5V
C12 - Nothing
C13 - Nothing
So unless "nothing" indicates bad trace wires/soldering pads and not busted capacitors, this definitely needs a recap. The question is is that preventing the screen/ROM from engaging...?
I also pick up voltage (maybe a little less than 5V; at the moment I'm doing this somewhat manually - or digitally in the denotative sense...) at both the RAM and ROM, which is a tentatively good sign.
C9 and C13 are involved in Horizontal Sweep (C12 is also in that circuit - a dampener) I think. So perhaps their failure prevents the screen from working. However that shouldn't affect the ROM (?). I'm concerned that recapping will just give me a blank albeit phosphorescent screen with no processor or ROM activity.
(I didn't control for polarity so I'm just listing voltages)
Disk Port Pins 7/8 - 12V
Pin 5 (the 5V) - Nothing
UK4/6 both 5V
UC8 - 12 V
C1 - 5V
C3 - 5V
C4 - 5V
C5 - 5V
C6 - 0.5V
C7 - 5V
C8 - 5V
C9 - Nothing
C11 - 5V
C12 - Nothing
C13 - Nothing
So unless "nothing" indicates bad trace wires/soldering pads and not busted capacitors, this definitely needs a recap. The question is is that preventing the screen/ROM from engaging...?
I also pick up voltage (maybe a little less than 5V; at the moment I'm doing this somewhat manually - or digitally in the denotative sense...) at both the RAM and ROM, which is a tentatively good sign.
C9 and C13 are involved in Horizontal Sweep (C12 is also in that circuit - a dampener) I think. So perhaps their failure prevents the screen from working. However that shouldn't affect the ROM (?). I'm concerned that recapping will just give me a blank albeit phosphorescent screen with no processor or ROM activity.
Or does the lack of voltage at the capacitors actually signify trace failures?
You have to recap. Period. At this point its the only way to continue.
Agreed. I have to wait for the soldering iron I just ordered.